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Outdoor digital information display (DID) installed near public areas has become a very popular medium of communication. Cooling performance of an outdoor DID system has become a critical issue from increasing system temperature due to heat generation at the back panel, in addition to irradiation from the sunlight. Gap distance between the heating plate and glass could control the main heat transfer rate considering its positive or negative effect on the pressure and temperature gradient at the wall. Additional reduction of maximum surface temperature can be achieved using tapered geometry with increased inlet gap distance, as well as guide vane installation at the system exit to lower pressure loss. Full system optimization has also been performed, including correlation for tapered geometry and guide vane effect. With system optimization, we can find the optimal gap clearance of parallel or tapered geometry for best performance.

The in-mold labeling (IML) process has become a popular choice for the exterior decoration of many mobile devices due to its capability of rich color representation with a relatively easy manufacturing procedure. A molten polymer is injected into a cavity where pre-decorated film has been initially inserted. A heterogeneous characteristic of involved material coupled with various processing parameters can induce defects of the final product such as film delamination, wash-out, and flow-mark. In this study, major controlling parameters for the deformation of the final product have been identified with the design of experiment (DOE) method using several nondimensional quantities of temperature, material property, and thickness ratio. MOLDFLOW and ABAQUS software has been simultaneously used to simulate the injection process and thermal impact process, respectively. We found that the thickness ratio is a critical factor on final deformation, and the material property ratio has a relatively minor effect.